param(
  [Parameter(Mandatory)][string]$OutputDirectory,
  [ValidateRange(4,8)][int]$Pairs = 4,
  [string]$PythonExecutable,
  [ValidateRange(0,9223372036854775807)][long]$ProbeAffinityMask = 0,
  [switch]$AnalyzeOnly
)
# One controlled batch of OFF/WPR-ON fixed-work synthetic runs; no Wii/NAND.
# WPR requires an elevated PowerShell. Every run gets a unique directory.
$ErrorActionPreference = 'Stop'
$p1Repo = [IO.Path]::GetFullPath((Join-Path $PSScriptRoot '../..'))
$p1Root = [IO.Path]::GetFullPath($(if ([IO.Path]::IsPathRooted($OutputDirectory)) {
  $OutputDirectory
} else {
  Join-Path $p1Repo $OutputDirectory
}))
if ($PythonExecutable) {
  $p1Python = (Resolve-Path -LiteralPath $PythonExecutable).Path
} else {
  $p1Candidates = @(Get-Command python.exe -All -ErrorAction SilentlyContinue |
    Where-Object { $_.Source -notlike '*\WindowsApps\*' } |
    Select-Object -ExpandProperty Source)
  $p1Candidates += 'C:\msys64\mingw64\bin\python.exe'
  foreach ($p1Candidate in $p1Candidates) {
    if ($p1Candidate -and (Test-Path -LiteralPath $p1Candidate)) {
      $p1Python = $p1Candidate
      break
    }
  }
}
if (-not $p1Python) {
  throw 'Python was not found before capture. Pass -PythonExecutable with the path to a working python.exe.'
}
& $p1Python --version | Out-Null
if ($LASTEXITCODE) { throw "Python could not start: $p1Python" }
$p1AlreadyExists = Test-Path -LiteralPath $p1Root
if ($AnalyzeOnly -and -not $p1AlreadyExists) { throw "Existing batch not found: $p1Root" }
if (-not $AnalyzeOnly -and $p1AlreadyExists) {
  throw 'Use a NEW batch directory for capture. Pass -AnalyzeOnly to compare existing captures.'
}
$p1Probe = Join-Path $p1Repo '.starlet_diag_p1/Binaries/Tests/TraceProbeP1.exe'
$p1Network = Join-Path $p1Repo '.starlet_diag_p1/Binaries/Network'
$p1Decoder = Join-Path $p1Repo '.starlet-profile/P1-tools/DecodeP1.exe'
if (-not $AnalyzeOnly) {
  foreach ($p1Required in @($p1Probe, $p1Network, $p1Decoder)) {
    if (-not (Test-Path -LiteralPath $p1Required)) { throw "Missing dependency: $p1Required" }
  }
  $p1Drive = [IO.DriveInfo]::new([IO.Path]::GetPathRoot($p1Root))
  if ($p1Drive.AvailableFreeSpace -lt 9GB) { throw 'Need 4 GiB batch budget plus 5 GiB reserve.' }
  New-Item -ItemType Directory -Path $p1Root | Out-Null
}
$p1Runs = @()
for ($p1Index = 1; $p1Index -le $Pairs; ++$p1Index) {
  $p1Off = Join-Path $p1Root "off-$p1Index"
  $p1On = Join-Path $p1Root "wpr-on-$p1Index"
  if (-not $AnalyzeOnly) {
    Write-Output "Pair $p1Index/${Pairs}: fixed-work OFF"
    & (Join-Path $PSScriptRoot 'Capture-Private-P1.ps1') -OutputDirectory $p1Off -NoTrace `
      -ProbeAffinityMask $ProbeAffinityMask
    Write-Output "Pair $p1Index/${Pairs}: fixed-work WPR ON"
    & (Join-Path $PSScriptRoot 'Capture-P1.ps1') -OutputDirectory $p1On -Seconds 60 `
      -ProbeExecutable $p1Probe `
      -ProbeArguments @((Join-Path $p1On 'synthetic.journal'), $p1Network) `
      -ProbeAffinityMask $ProbeAffinityMask
    $p1Decoded = & $p1Decoder (Join-Path $p1On 'capture.etl') `
      (Join-Path $p1On 'native-events.jsonl')
    $p1DecodeExit = $LASTEXITCODE
    $p1Decoded | Out-File -LiteralPath (Join-Path $p1On 'decoder-summary.json') -Encoding utf8
    if ($p1DecodeExit) { throw "Pair $p1Index has ETW loss or native decode errors." }
  }
  $p1Runs += $p1Off, $p1On
}
$p1Comparison = Join-Path $p1Root 'comparison.json'
if (Test-Path -LiteralPath $p1Comparison) {
  throw "Comparison already exists and will not be overwritten: $p1Comparison"
}
& $p1Python (Join-Path $PSScriptRoot 'compare_p1.py') @p1Runs --output $p1Comparison
if ($LASTEXITCODE) { throw 'Fixed-work comparison failed; no Wii run was started.' }
Write-Output "Overhead batch finished: $p1Comparison"